How it grew: National Gift Card acts as a go-between for companies giving prepaid gift cards to employees and customers and the restaurants and retailers offering the cards. The company negotiates discounts of up to 10% from the vendors, ranging from steakhouse chains like Ruth's Chris to merchants such as Home Depot, and keeps a small slice of that for itself. But the business this year is moving online, with e-cards now being sent directly to recipients. "There is an environmental savings in this," President Adam Van Witzenburg, 41, says. "Plastic is a petroleum-based material. In the future our customers won't be throwing away cards once they've been used. They like that."